Kaoru is a 17-year-old virgin whose main hobby is S&M; in particular, the purchase of S&M gear since he doesn't have a partner. Nana is his perfect next door neighbor. The two have been close since the first grade due to the fact they both have single parents who work a lot. Kaoru is secretly in love with Nana and likes to fantasize about her in tandem with his S&M gear. One day his mother decides to get rid of all his gear and asks Nana to hold on to it overnight so Kaoru won't be able to find it and hide it. Later that night Nana inadvertently locks herself into one of Kaoru's leather outfits that she had been trying on "for size" and is forced to ask Kaoru for help unlocking it...